/*
 * Copyright 2021 TiKV Project Authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

package com.webank.tikv.common;

import java.io.Serializable;
import java.util.Objects;

/**
 * TiTimestamp is the timestamp returned by timestamp oracle inside placement driver
 */
public class TiTimestamp implements Serializable {
    private static final int PHYSICAL_SHIFT_BITS = 18;

    private final long physical;
    private final long logical;

    public TiTimestamp(long p, long l) {
        this.physical = p;
        this.logical = l;
    }

    public static long extractPhysical(long ts) {
        return ts >> PHYSICAL_SHIFT_BITS;
    }

    public long getVersion() {
        return (physical << PHYSICAL_SHIFT_BITS) + logical;
    }

    public long getPhysical() {
        return physical;
    }

    public long getLogical() {
        return logical;
    }

    public TiTimestamp getPrevious() {
        return new TiTimestamp(physical, logical - 1);
    }

    @Override
    public boolean equals(Object other) {
        if (other == this) {
            return true;
        }
        if (!(other instanceof TiTimestamp)) {
            return false;
        }
        return getVersion() == ((TiTimestamp) other).getVersion();
    }

    @Override
    public int hashCode() {
        return Objects.hash(getVersion());
    }

    @Override
    public String toString() {
        return "TiTimestamp(" + getVersion() + ")";
    }
}
